package com.komorebi.friends.service.impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.bean.copier.CopyOptions;
import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.collection.CollectionUtil;
import cn.hutool.core.lang.Pair;
import cn.hutool.core.util.StrUtil;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.google.common.reflect.TypeToken;
import com.google.gson.Gson;
import com.komorebi.friends.common.ErrorCode;
import com.komorebi.friends.constant.CommonConstant;
import com.komorebi.friends.constant.RedisConstant;
import com.komorebi.friends.exception.BusinessException;
import com.komorebi.friends.exception.ThrowUtils;
import com.komorebi.friends.model.dto.user.UserLoginRequest;
import com.komorebi.friends.model.dto.user.UserQueryRequest;
import com.komorebi.friends.model.dto.user.UserUpdateMyRequest;
import com.komorebi.friends.model.entity.User;
import com.komorebi.friends.model.enums.UserRoleEnum;
import com.komorebi.friends.model.vo.LoginUserVO;
import com.komorebi.friends.model.vo.UserVO;
import com.komorebi.friends.service.UserService;
import com.komorebi.friends.mapper.UserMapper;
import com.komorebi.friends.utils.AlgorithmUtils;
import com.komorebi.friends.utils.SqlUtils;
import io.swagger.models.auth.In;
import lombok.extern.slf4j.Slf4j;
import me.chanjar.weixin.common.bean.WxOAuth2UserInfo;
import org.apache.commons.lang3.StringUtils;
import org.elasticsearch.search.aggregations.metrics.InternalGeoBounds;
import org.springframework.beans.BeanUtils;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;
import org.springframework.util.DigestUtils;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.util.*;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;

import static com.komorebi.friends.constant.CommonConstant.VERIFY_CODE;
import static com.komorebi.friends.constant.UserConstant.USER_LOGIN_STATE;

/**
* @author LX-MF
* @description 针对表【user(用户)】的数据库操作Service实现
* @createDate 2024-09-21 15:19:50
*/
@Service
@Slf4j
public class UserServiceImpl extends ServiceImpl<UserMapper, User>
    implements UserService{

    @Resource
    UserMapper userMapper;

    @Resource
    StringRedisTemplate stringRedisTemplate;

    /**
     * 盐值，混淆密码
     */
    public static final String SALT = "yupi";

    @Override
    public long userRegister(String userAccount, String userPassword, String checkPassword) {
        // 1. 校验
        if (StringUtils.isAnyBlank(userAccount, userPassword, checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户账号过短");
        }
        if (userPassword.length() < 8 || checkPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户密码过短");
        }
        // 密码和校验密码相同
        if (!userPassword.equals(checkPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "两次输入的密码不一致");
        }
        synchronized (userAccount.intern()) {
            // 账户不能重复
            QueryWrapper<User> queryWrapper = new QueryWrapper<>();
            queryWrapper.eq("userAccount", userAccount);
            long count = this.baseMapper.selectCount(queryWrapper);
            if (count > 0) {
                throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号重复");
            }
            // 2. 加密
            String encryptPassword = DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes());
            // 3. 插入数据
            User user = new User();
            user.setUserAccount(userAccount);
            user.setUserPassword(encryptPassword);
            boolean saveResult = this.save(user);
            if (!saveResult) {
                throw new BusinessException(ErrorCode.SYSTEM_ERROR, "注册失败，数据库错误");
            }
            return user.getId();
        }
    }

    @Override
    public LoginUserVO userLogin(UserLoginRequest userLoginRequest, HttpServletRequest request) {
        // 0. 验证码
        String code = userLoginRequest.getCode();
        String verify_code = (String) request.getSession().getAttribute(VERIFY_CODE);
        if(StrUtil.isBlank(code) || !code.equals(verify_code)){
            throw new BusinessException(ErrorCode.PARAMS_ERROR,"验证码错误");
        }
        String userAccount = userLoginRequest.getUserAccount();
        String userPassword = userLoginRequest.getUserPassword();
        // 1. 校验
        if (StringUtils.isAnyBlank(userAccount, userPassword)) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "参数为空");
        }
        if (userAccount.length() < 4) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "账号错误");
        }
        if (userPassword.length() < 8) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "密码错误");
        }
        // 2. 加密
        String encryptPassword = DigestUtils.md5DigestAsHex((SALT + userPassword).getBytes());
        // 查询用户是否存在
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("userAccount", userAccount);
        queryWrapper.eq("userPassword", encryptPassword);
        User user = this.baseMapper.selectOne(queryWrapper);
        // 用户不存在
        if (user == null) {
            log.info("user login failed, userAccount cannot match userPassword");
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "用户不存在或密码错误");
        }
        // 3. 记录用户的登录态
        request.getSession().setAttribute(USER_LOGIN_STATE, user);
        // 4. 写入缓存 , 使用哈希结构存储
        String sessionId = request.getSession().getId();
        String key = RedisConstant.REDIS_LOGIN_USERINFO_PREFIX + sessionId;
        writeRedisUser(key, user);
        return this.getLoginUserVO(user);
    }

    /**
     * 写入 redis 里
     * @param key  redis 的键
     * @param user  用户信息
     */
    @Override
    public void writeRedisUser(String key, User user) {
        Map<String, Object> toMapUser = BeanUtil.beanToMap(user, new HashMap<>(),
                CopyOptions.create()
                        .setIgnoreNullValue(false)
                        .setFieldValueEditor((fieldName, fieldValue) -> {
                            if (fieldValue != null) {
                                return fieldValue.toString();
                            }
                            return "";
                        }));
        stringRedisTemplate.opsForHash().putAll(key, toMapUser);
        //设置有效期
        stringRedisTemplate.expire(key, RedisConstant.LOGIN_USER_TTL, TimeUnit.MINUTES);
    }

    @Override
    public LoginUserVO userLoginByMpOpen(WxOAuth2UserInfo wxOAuth2UserInfo, HttpServletRequest request) {
        String unionId = wxOAuth2UserInfo.getUnionId();
        String mpOpenId = wxOAuth2UserInfo.getOpenid();
        // 单机锁
        synchronized (unionId.intern()) {
            // 查询用户是否已存在
            QueryWrapper<User> queryWrapper = new QueryWrapper<>();
            queryWrapper.eq("unionId", unionId);
            User user = this.getOne(queryWrapper);
            // 被封号，禁止登录
            if (user != null && UserRoleEnum.BAN.getValue().equals(user.getUserRole())) {
                throw new BusinessException(ErrorCode.FORBIDDEN_ERROR, "该用户已被封，禁止登录");
            }
            // 用户不存在则创建
            if (user == null) {
                user = new User();
                user.setUnionId(unionId);
                user.setMpOpenId(mpOpenId);
                user.setUserAvatar(wxOAuth2UserInfo.getHeadImgUrl());
                user.setUserName(wxOAuth2UserInfo.getNickname());
                boolean result = this.save(user);
                if (!result) {
                    throw new BusinessException(ErrorCode.SYSTEM_ERROR, "登录失败");
                }
            }
            // 记录用户的登录态
            request.getSession().setAttribute(USER_LOGIN_STATE, user);
            return getLoginUserVO(user);
        }
    }

    /**
     * 获取当前登录用户
     *
     * @param request
     * @return
     */
    @Override
    public User getLoginUser(HttpServletRequest request) {
        // 先判断是否已登录
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User currentUser = (User) userObj;
        if (currentUser == null || currentUser.getId() == null) {
            throw new BusinessException(ErrorCode.NOT_LOGIN_ERROR);
        }
        //  从缓存拿
        String key = RedisConstant.REDIS_LOGIN_USERINFO_PREFIX + request.getSession().getId();
        Map<Object, Object> entries = stringRedisTemplate.opsForHash().entries(key);
        if(entries.isEmpty()){
            // 从数据库查询
            long userId = currentUser.getId();
            currentUser = this.getById(userId);
            if (currentUser == null) {
                throw new BusinessException(ErrorCode.NOT_LOGIN_ERROR);
            }
            // 写入缓存
            writeRedisUser(key, currentUser);
            return currentUser;
        }
        // 将缓存的map转成对象
        return BeanUtil.fillBeanWithMap(entries, new User(), false);
    }

    /**
     * 获取当前登录用户（允许未登录）
     *
     * @param request
     * @return
     */
    @Override
    public User getLoginUserPermitNull(HttpServletRequest request) {
        // 先判断是否已登录
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User currentUser = (User) userObj;
        if (currentUser == null || currentUser.getId() == null) {
            return null;
        }
        // 从数据库查询（追求性能的话可以注释，直接走缓存）
        long userId = currentUser.getId();
        return this.getById(userId);
    }

    /**
     * 是否为管理员
     *
     * @param request
     * @return
     */
    @Override
    public boolean isAdmin(HttpServletRequest request) {
        // 仅管理员可查询
        Object userObj = request.getSession().getAttribute(USER_LOGIN_STATE);
        User user = (User) userObj;
        return isAdmin(user);
    }

    @Override
    public boolean isAdmin(User user) {
        return user != null && UserRoleEnum.ADMIN.getValue().equals(user.getUserRole());
    }

    /**
     * 用户注销
     *
     * @param request
     */
    @Override
    public boolean userLogout(HttpServletRequest request) {
        if (request.getSession().getAttribute(USER_LOGIN_STATE) == null) {
            throw new BusinessException(ErrorCode.OPERATION_ERROR, "未登录");
        }
        // 移除登录态
        String key = RedisConstant.REDIS_LOGIN_USERINFO_PREFIX + request.getSession().getId();
        request.getSession().removeAttribute(USER_LOGIN_STATE);
        stringRedisTemplate.delete(key);
        return true;
    }

    @Override
    public LoginUserVO getLoginUserVO(User user) {
        if (user == null) {
            return null;
        }
        LoginUserVO loginUserVO = new LoginUserVO();
        BeanUtils.copyProperties(user, loginUserVO);
        return loginUserVO;
    }

    @Override
    public UserVO getUserVO(User user) {
        if (user == null) {
            return null;
        }
        UserVO userVO = new UserVO();
        BeanUtils.copyProperties(user, userVO);
        return userVO;
    }

    @Override
    public List<UserVO> getUserVO(List<User> userList) {
        if (CollUtil.isEmpty(userList)) {
            return new ArrayList<>();
        }
        return userList.stream().map(this::getUserVO).collect(Collectors.toList());
    }

    @Override
    public QueryWrapper<User> getQueryWrapper(UserQueryRequest userQueryRequest) {
        if (userQueryRequest == null) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR, "请求参数为空");
        }
        Long id = userQueryRequest.getId();
        String unionId = userQueryRequest.getUnionId();
        String mpOpenId = userQueryRequest.getMpOpenId();
        String userName = userQueryRequest.getUserName();
        String userProfile = userQueryRequest.getUserProfile();
        String userRole = userQueryRequest.getUserRole();
        String gender = userQueryRequest.getGender();
        String email = userQueryRequest.getEmail();
        String sortField = userQueryRequest.getSortField();
        String sortOrder = userQueryRequest.getSortOrder();

        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq(id != null, "id", id);
        queryWrapper.eq(StringUtils.isNotBlank(unionId), "unionId", unionId);
        queryWrapper.eq(StringUtils.isNotBlank(mpOpenId), "mpOpenId", mpOpenId);
        queryWrapper.eq(StringUtils.isNotBlank(userRole), "userRole", userRole);
        queryWrapper.like(StringUtils.isNotBlank(userProfile), "userProfile", userProfile);
        queryWrapper.like(StringUtils.isNotBlank(userName), "userName", userName);
        queryWrapper.eq( StringUtils.isNotBlank(gender),"gender", gender);
        queryWrapper.like(StringUtils.isNotBlank(email), "email", email);
        queryWrapper.orderBy(SqlUtils.validSortField(sortField), sortOrder.equals(CommonConstant.SORT_ORDER_ASC),
                sortField);
        return queryWrapper;
    }

    @Override
    public User getSafetyUser(User user){
        User safetyUser = new User();
        Long id = user.getId();
        String tags = user.getTags();
        String userName = user.getUserName();
        String userAvatar = user.getUserAvatar();
        String userProfile = user.getUserProfile();
        String userRole = user.getUserRole();
        Date createTime = user.getCreateTime();
        safetyUser.setId(id);
        safetyUser.setTags(tags);
        safetyUser.setUserName(userName);
        safetyUser.setUserAvatar(userAvatar);
        safetyUser.setUserProfile(userProfile);
        safetyUser.setUserRole(userRole);
        safetyUser.setCreateTime(createTime);
        return safetyUser;
    }

    /**
     *  用数据库做搜索
     * @param tagList  搜索的标签 / 用户要有的标签
     * @return
     */
//    @Override
//    public List<User> searchUserByTags(List<String> tagList){
//        //1.判空
//        if(CollectionUtil.isEmpty(tagList)){
//            throw new BusinessException(ErrorCode.PARAMS_ERROR);
//        }
//        // 2.拼接查询
//        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
//        for (String tag : tagList) {
//            queryWrapper = queryWrapper.like("tags",tag);  //自动加百分号
//        }
//        List<User> users = userMapper.selectList(queryWrapper);
//        // 3.返回结果
//        return users.stream().map(this::getSafetyUser).collect(Collectors.toList());
//    }

    /**
     *  用内存做搜索
     * @param tagList  搜索的标签 / 用户要有的标签
     * @return
     */
    @Override
    public List<User> searchUserByTags(List<String> tagList){
        //1.判空
        if(CollectionUtil.isEmpty(tagList)){
            throw new BusinessException(ErrorCode.PARAMS_ERROR);
        }
        // 2.拿到所有的用户信息
        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
        List<User> users = userMapper.selectList(queryWrapper);
        // 3.在内存中判断是否包含要求的标签（就是在代码里写）
        Gson gson = new Gson();
        // 3.1 Json 转成集合类型  3.2 过滤掉不全含有tagList的user 3.3 返回结果
        return users.parallelStream().filter(user -> {
            String tags = user.getTags();
            if(StrUtil.isBlank(tags)) return false;
            Set<String> tagNames = gson.fromJson(tags, new TypeToken<Set<String>>(){}.getType());
            tagNames = Optional.ofNullable(tagNames).orElse(new HashSet<>());
            for (String tag : tagList) {
                if(!tagNames.contains(tag)) return false;
            }
            return true;
        }).map(this::getSafetyUser).collect(Collectors.toList());
    }

    /**
     * 更新用户信息
     * @param userUpdateMyRequest
     * @param request
     */
    @Override
    public void updateMyUser(UserUpdateMyRequest userUpdateMyRequest, HttpServletRequest request) {
        User loginUser = this.getLoginUser(request);
        User user = new User();
        // 2.将请求里的参数都放入 user 里
        BeanUtils.copyProperties(userUpdateMyRequest, user);
        // 1.设置 id
        Long id = loginUser.getId();
        user.setId(id);
        // 3.调用 service 里的更新方法
        boolean result = this.updateById(user);
        // 4. 更新缓存
        String key = RedisConstant.REDIS_LOGIN_USERINFO_PREFIX + request.getSession().getId();
        // 4.1从数据库查询
        User currentUser = this.getById(id);
        if (currentUser == null) {
            throw new BusinessException(ErrorCode.PARAMS_ERROR);
        }
        // 4.2写入缓存
        this.writeRedisUser(key, currentUser);
        ThrowUtils.throwIf(!result, ErrorCode.OPERATION_ERROR);
    }

    /**
     * 匹配用户
     * @param loginUser 用户
     * @return
     */
    @Override
    public List<User> getMatchUsers(Long num,User loginUser) {
        //当前用户的标签
        Long userId = loginUser.getId();
        User user = getById(userId);
        String tags = user.getTags();
        Gson gson = new Gson();
        List<String> tagList = gson.fromJson(tags, new TypeToken<List<String>>() {
        }.getType());
        //取出所有用户，调用AlgorithmUtils里的函数
        List<User> userList = this.list();
        //用一个pair<distance,User>来存储与其它所有用户的距离
        List<Pair<Integer,User>> userDistancePairList = new ArrayList<>();
        for (User user1 : userList) {
            String user1Tags = user1.getTags();
            if(StrUtil.isBlank(user1Tags) || user1.getId().equals(userId) ) continue;
            List<String> userTags = gson.fromJson(user1Tags, new TypeToken<List<String>>() {
            }.getType());
            int distance = AlgorithmUtils.minDistance(userTags, tagList);
            userDistancePairList.add(new Pair<>(distance,getSafetyUser(user1)));
        }
        //再根据score把信息排序，距离小的在前面
        List<Pair<Integer, User>> sortedPairList = userDistancePairList.stream().sorted((a, b) ->
                (int) (a.getKey() - b.getKey())
        ).limit(num).collect(Collectors.toList());
        List<User> collect = sortedPairList.stream().map(pair -> pair.getValue()).collect(Collectors.toList());

        return collect;
    }



}




